I see a lot of leather, plastic, and some paper mache in there. Let's start with the head. take a large beach ball, paper mache it. pop the ball inside and make a hole for your head to go in as well as the holes for the part to see out from and other areas.
Resin the head and apply bondo or another coating material to get the details on the head. As for the tank on the back that might take you a bit of sourcing to find something similar. For the frame on the back first check with sign shops to see if they have any scrap sintra most of the time you can get that stuff fairly cheap or free, if not order it.
You can also use some of it for making the armor I see on the forearms, the neckpiece, leg braces and the shoulder. For the colored syringes, you can look at some of the stores in your area to see if they have one of those big enough if not the you can definatly get them without the needle off a place like eBay. fill with dyed liquid and seal the tubes to prevent leaking.
That's about as best as I can help at this point.